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Early Infrared Spectral Development of V1187 Scorpii (Nova Scorpii 2004 No. 2)
We report on an unprecedented infrared time series of spectra of V1187Sco, a very fast ONeMg nova. The observations covered a 56 day period(2004 August 6-September 30) starting 2 days after the nova's peakbrightness. Time evolution of the spectra revealed changing linestrengths and profiles on timescales of less than a day to weeks as thenova evolved from early postmaximum to early coronal phases. When ourground-based optical and Spitzer Space Telescope data were combined, thewavelength coverage of 0.38-36 μm allowed an accurate spectral energydistribution to be derived when it was about 6 weeks after outburst.Developing double structure in the He I lines showed them changing fromnarrow to broad in only a few days. Using the O I lines in combinationwith the optical spectra, we derived a reddening of E(B-V)=1.56+/-0.08and a distance of 4.9+/-0.5 kpc. Modeling of the ejected materialstrongly suggested that it was geometrically thick withΔR/R=0.8-0.9 (more of a wind than a shell) and a low fillingfactor of order a few percent. The line shapes were consistent with acylindrical jet, bipolar, or spherical Hubble flow expansion with amaximum speed of about -3000 km s-1. The central peakappeared to be more associated with the spherical component, while thetwo peaks (especially in Hβ) suggested a ring with either a lowervelocity component or with its axis inclined to the line of sight.
| Far-Ultraviolet Stellar Photometry: Fields Centered on rho Ophiuchi and the Galactic Center
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1996ApJS..104..101S&db_key=AST
| Far-ultraviolet stellar photometry: Fields in Sagittarius and Scorpius
Far-ultraviolet photometry for 741 objects in a field in Sagittariuscentered near M8 and 541 objects in a field centered near sigma Scorpiiis presented. These data were extracted from electographic imagesobtained with two cameras during a shuttle flight in 1991 April/May. Thecameras provided band passes with lambdaeff = 1375 A andlambdaeff = 1781 A. Synthetic colors show that these bandsare sensitive to effective temperature for hot stars. Our measurementswere placed on a quantitative far-ultraviolet magnitude scale byconvolving the spectra of stars observed by IUE with our cameras'spectral response functions. Fifty-eight percent of the ultravioletobjects were identified with visible stars using the SIMBAD databasewhile another 40% of the objects are blends of early type stars tooclose together to separate with our resolution. Our photometry iscompared with that from the TD-1, OAO 2, and ANS satellites and the S201(Apollo 16) far-ultraviolet camera and found to agree at the level of afew tenths of a magnitude. Unlike previous studies, almost half of theidentified visual counterparts to the ultraviolet objects are early Bstars. A plot of distance modulus against ultraviolet color excessreveals a significant population of stars with strong ultravioletexcess.
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Membro dei seguenti gruppi:
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Osservazione e dati astrometrici
| Costellazione: | Sagittario |
| Ascensione retta: | 17h48m25.56s |
| Declinazione: | -16°49'37.9" |
| Magnitudine apparente: | 8.368 |
| Distanza: | 297.619 parsec |
| Moto proprio RA: | -3.2 |
| Moto proprio Dec: | -11.5 |
| B-T magnitude: | 8.573 |
| V-T magnitude: | 8.385 |
Cataloghi e designazioni:
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